CVE-2021-21020: Magento Commerce Improper Access Control Vulnerability

Severity: medium (CVSS 4.3 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-02-11 · updated 2026-06-17
Weakness: CWE-284

Description

Magento versions 2.4.1 (and earlier), 2.4.0-p1 (and earlier) and 2.3.6 (and earlier) are vulnerable to an access control bypass vulnerability in the Login as Customer module. Successful exploitation could lead to unauthorized access to restricted resources.

Affected products

Adobe Magento Commerce: before 2.3.6; 2.3.6, 2.4.0, 2.4.0-p1, 2.4.1 — fixed in 2.3.6

How to fix

Upgrade to a fixed version: Adobe Magento Commerce 2.3.6. Check the vendor advisory for mitigations.

References

https://helpx.adobe.com/security/products/magento/apsb21-08.html
https://helpx.adobe.com/security/products/magento/apsb21-08.html

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